If a boat is a magic carpet for dreams, then a trailer is a magic carpet for a boat.

Quite a few issues of safety, in the yachting world, come down to the preferences of the skipper and crew. There will never be universal agreement on how (or if) to use tethers, or on where a life raft should be kept, or on whether an extra EPIRB is a better investment than an AIS-B transponder upgrade.

We can, however, apply some general principles of risk analysis and risk mitigation at the design stage. The maritime world already has some ways of figuring this out, but for today, I think I'll shake things up a bit with some principles from a different field: ionizing radiation.

The last post in our series on yacht stability looked at the static case. We saw that a yacht's response to heeling forces can be described by a stability curve, the shape of which tells us a lot about the boat's purpose, sailing characteristics and seaworthiness.

A real yacht in a real situation is of course far from being a static case. The static stability curve is one of our best tools for quantitatively comparing different designs, and I don't mean to denigrate its importance. In practice, though, dynamic factors can often have a bigger effect on the actual stability of the boat as it relates to safety, seaworthiness and comfort.